[the_duke]

Please correct me if I'm off base here, but isn't a big part of the whole virtual-dom abstraction performance?

Direct DOM updates are slow (rerender), diffing and smart patching much faster. There must be a reason for virtual doms becoming so popular, even for frameworks that don't have a 'functional' approach like React.

[rich_harris]

Great question! It's a very common misconception that an app that uses virtual DOM diffing somehow manages to be faster than an app that manipulates the DOM directly.

Re-rendering your entire app (i.e. creating all the nodes from scratch with innerHTML or document.createElement) is too slow for a lot of apps, and is a bad idea for lots of other reasons (losing state in form elements, etc). Virtual DOM just gives you a way to write your app as though you were re-rendering it from scratch, while still being fast enough that you can get away with it.

Svelte is significantly faster than React according to https://github.com/krausest/js-framework-benchmark, because it's taking a more direct approach to the same goal — updating existing elements or only creating/destroying them as necessary. It's also faster than Ember, Angular, Vue, etc. It's not yet quite as fast as Inferno, but it uses less memory.

[tobr]

Virtual DOMs are used to make the rerender-everything-all-the-time approach acceptably fast, which is desirable since that approach tends to lead to nice UI code with few state related bugs. Still, this is a pretty costly way to update the UI, as the virtual DOM causes a lot of memory churn.

[proyb2]

Agreed with Rich, it's a misconception that virtual-dom is faster, web browsers have made significant improvement to DOM. There must be a reason why vanilla Javascript is fastest than most virtual-dom.

Inferno-1.1.0 have an error at runtime, could not test JS Framework right now. Sveltejs works.

[trueadm]

What issue did you have with Inferno, would mind reporting it please so we can fix it? :)

[proyb2]

Inferno in JS framework replies use beta, I guess that broken.